Tell your doctor you don't like it and maybe try something else. It often takes time to match with a med that works for you. One size doesn't fit all :-)
I'm working with my doctor with my thyroid med, not liking it. They try different things, see what works, it's not an exact science. Sorry you're scared.
http://www.nimh.nih.gov/health/publi...reatment.shtml